In a large dutch oven, heat 2 tablespoons of olive oil over medium-high heat. Add chicken, chili powder, and cumin. Season with salt and pepper, to taste. Cook the chicken, stirring, until no longer pink, about 5 minutes. Transfer with a slotted spoon to a large bowl.Add the remaining 2 tablespoons of olive oil to the pot. Add apples and onion. Cook, stirring, until softened. About 6-7 minutes. Transfer to the same bowl as the chicken.In the same pot, melt the butter over medium-low heat. Whisk in the flour for 1 minute, and then whisk in 2 cups of chicken stock and milk, until thickened, about 3-4 minutes.Stir in the chicken-apple mixture and beans, bring to a simmer. If the chili is too thick, add remaining ¼ cup stock or as needed. Then stir in the cheese until melted.Serve with your favorite toppings: sour cream, scallions, cilantro, fresh salsa, avocado, tortilla chips.